Journal of Clinical Trials
Open Access

COVID-19 Pandemic in India: Chronological Comparison of the Regional Heterogeneity in the Progression of the Pandemic and Gaps in Mitigation Strategies

Satabdi Datta¹, Neloy Kumar Chakroborty², Deepinder Sharda¹, Komal Attri^1,3 and Diptiman Choudhury^{1,3* *}Correspondence: Diptiman Choudhury, School of Chemistry and Biochemistry, Thapar Institute of Engineering and Technology, Patiala, Punjab, 147004, India, Tel: +91-8196949843, Email:

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Abbreviations

COVID-19: Coronavirus Disease 2019; NR: Northern Region; CR: Central Region; WR: Western Region; ER: Eastern Region; NER: North Eastern Region; SR: Southern Region; UT: Union Territory; CCR: Cumulative Case Rate; CDR: Cumulative Death Rate; CFR: Case Fatality Ratio; SARS CoV-2: Severe Acute Respiratory Syndrome Coronavirus-2; LAGE: Legislative Assembly General Election; WHO: World Health Organization

Introduction

India is currently the second-largest contributor of total COVID-19 cases of the world, accounting for about 16% of the total cases and around 9% of the deaths worldwide [1]. The state of Kerala has reported the first case of COVID-19 in India on January 30^th, 2020 [2]. Thereafter, from March 2020, the number of active cases started to rise at a rapid pace. Amid this crisis, the Government of India announced a nationwide lockdown with implementations of measures for public health, nevertheless, the COVID-19 cases started rising once again after the first phase of unlocking, from May 31^st, 2020 [3]. In most of the states, cases started to surge from June 2020, which reached their respective maxima in the middle of September 2020 [4]. The first wave however subsided towards the end of January 2021 which led to the withdrawal of several restrictions on social and political gatherings [5]. However, the consequence of this relaxation soon turned out to be catastrophic as the second wave of COVID-19 pandemic commenced from the middle of February 2021, which compelled the state governments to implement lockdown-like restrictions again [6,7]. The emergence of new indigenous and international mutants of the SARS-CoV-2 virus was accessed as one of the major reasons for the steep rise in cases and fatalities in the second wave [8,9].

The Indian subcontinent is characterized by diverse geographical and demographical regions, populated by heterogeneous cultural, political, linguistic, and ethnic groups of people covering an area of 3.28 million square kilometers with a total population of about 138 cores [10-14]. This huge diversity is likely to contribute to the visible heterogeneity in the progression patterns of the pandemic in each region of the country, which therefore demands the detailed analysis of chronological heterogeneity in the regional and state-specific infection rates, death rates, wave patterns, and testing capacities for a clear interpretation of the progression patterns of the two wave of the COVID-19 pandemic across the country. Previous publications on the effects of COVID-19 pandemic in India have either discussed the adverse impacts of the pandemic on the social structure, food security, mental and psychological health of the people, economic growth, and healthcare infrastructure or highlighted the gaps in communication between the health agencies and the Government of India, or demonstrated the containment measures, and the progression of the pandemic during the earlier part of the first wave [15-21]. However, no former study has reported the temporal dynamics of cases, deaths, and recoveries in the states and union territories of India and their respective contributions to the nation’s COVID-19 situation throughout the first and second wave of the pandemic. In this study, for the first time, we did a comprehensive analysis of the chronological changes in the patterns of progression of the pandemic during the first and second wave in each region of the country and its respective states and union territories-India comprises 28 states and 8 unions territories, divided along 6 administrative subdivisions, the Northern Region (NR), Central Region (CR), Western Region (WR), Eastern Region (ER), North Eastern Region (NER) and the Southern Region (SR) (Table 1 and Table 2) [22,23]. The analyses, revealing the differential progression patterns of the two waves, contribute significantly to the evaluations of the real scenario of the COVID-19 pandemic across the nation as well as disclose the gaps in pandemic mitigation strategies.

Table 1: First wave of COVID-19 in India: An account of the impact of the first wave of COVID-19, as of January 31st, 2021, in the different regions and their respective states and UT’s of the country and testing
ratios.

Table 2: Second Wave of COVID-19 in India (Till May 29^th, 2021): An account of the impact of the second wave in different regions and their respective states and union territories, and the testing ratio.

Materials and Methods

Study design and data sources

A detailed study of the COVID-19 infections and their related statistics in India was done for the periods, from January 30^th, 2020 to January 31^st, 2021 for the first wave, and from February 1^st, 2021 to May 29^th, 2021 for the second wave. The day, reporting the highest number of active cases was defined as the peak of the wave. The pandemic wave was defined by a phase of a rising number of COVID-19 cases with a definite peak, followed by a phase of the declining number of cases, or the trough period (in which the rates of new infections and active cases have declined significantly). The days of first reported infection, rising (a 10% consistent increase in the number of active cases) and declining phases of the two waves, peaks of the waves, numbers of new infections, death, recoveries along with the testing and demographical data for all the 6 administrative regions, comprising of 28 states and 8 union territories (UTs) of the country, were obtained from the online monitoring official website of the Government of India [4] and other national and international websites [24]. The numbers of monthly new cases, deaths, and recoveries for each state were calculated and the chronological (monthly) contributions of each administrative region of the subcontinent (contributions from all the states and union territories of the concerned region were summed up) to the nation's total number of new cases, deaths, and recoveries were calculated.

Statistical analysis

Extensive analysis was performed to establish the epidemiological parameters, such as CCR or cumulative case rate (cases per 1 lakh or 100000 populations), CDR or cumulative death rate (deaths per 1 lakh), CFR or case fatality ratio (number of deaths reported per number of cases reported × 100), and TPC or test per case (total number of tests/total number of cases) for both the first and second waves. These values were plotted on the Indian political map using https://mapchart.net/india.html to depict the heterogeneous progression of the pandemic in the states and UTs during the two waves. The weekly average numbers of new confirmed cases, active cases, and deaths were quantified by averaging the changes in numbers between the successive days over a week. The fold changes in average daily new cases for each month (before, during, and after LAGE) for the 5 states, which underwent elections, were calculated and compared with 5-other states that didn’t experience any major public gathering.

Discussion

The second wave of COVID-19 pandemic resulted in total unexpected disarrays in all states of the country. While the first wave caused a little over 1.08 crore infections and over 1.5 lakhs fatality in the whole country within 11 months, the ongoing second wave resulted in over 1.7 crore infections and nearly 2 lakhs fatalities in a span of merely 4 months. The daily average number of new cases during April 2021 was around 2.31 lakhs which soared to about 3.01 lakhs cases/day in May 2021, which are nearly 2.7 and 3.5 times the average daily cases (87,000 cases/day) of September 2020, when India reported its peak of the first wave. The CCR and CDR for the second wave were also found to elevate substantially in comparison to the first wave (Table 1), however, the CFR for both the waves did not show much variation for the majority of states (except for Maharashtra and Punjab) until May 29th, 2021 (Table 2). The advent of new and more infectious variants of the virus, inaccuracy in diagnosis, lack of testing, non-transparency in data sharing, low rate of vaccination, decreased rate of genome sequencing of the positive samples along with unchecked social, religious, and political gatherings, the inflexible attitude of the citizens (violating the containment protocols), and importantly, the serious lack of persistent measures to mitigate COVID-19, despite previous warnings, were held responsible for this unprecedented escalation of the pandemic in the country by many reports [15,32- 34]. Despite an increase in the daily test numbers, the test-to-case ratio has dropped in the majority of states during the second wave (Figure 3D and Table 2). Thus, the need of the hour is to accelerate the testing rates both in the rural and urban regions of the nation to get a clear picture of the infection scenario, which will aid to avert the nucleation of another catastrophic wave of the pandemic [35,36].

Our study comprehends that the Southern and Western regions were the major hotspots of the pandemic in both waves. The state of Karnataka and Tamil Nadu from the SR and Maharashtra from the WR showed consistently high numbers of infections and fatalities throughout the two waves. These results indicate that irrespective of the presence of the highly infectious B.1.617 Indian variant of the SARS-CoV-2 in these states during the second wave, shortfalls in the health systems and deficits in the implementations of COVID-19 restriction protocols may be responsible for the upsurge of the pandemic in these territories.

Although the data on demographical differences in infection are not made available to the public by the Ministry of Health and Family Welfare, Govt. of India, however, many recent reports have suggested that a notable difference between the first and second wave in the country is that the second wave affected a large portion of the pediatric group, which remained largely asymptomatic in the first wave [37]. As of the first week of April 2021 (between March 1st to April 4^th , 2021), it was reported that over 79,000 children were affected by the disease from the five states which include Maharashtra, Chattisgarh, Karnataka, Uttar Pradesh, and Delhi, of which over 60,000 cases were from Maharashtra [38], although the number of hospitalization among the children was only a handful. In India, the gap between the peaks of the two waves was about 7.5 months, which was a bit larger than the average gap of around 5 months reported for the majority of countries; however, the escalation of the second wave was far higher in this country than others [37]. At present, the second wave is in its declining phase for the majority of Indian states, albeit experts have suggested that unless the vaccination rate is accelerated, the country is set to face the 3^rd wave by the end of this year, which may affect the unvaccinated population in large numbers [39-42]. Thus, ramping up of the clinical trials of vaccines both for the pediatric and adult groups, strengthening of the health infrastructure of the nation, wide-scale genomic sequencing of the positive samples, monitoring of the progression of new cases, and strict implementation of COVID-19 appropriate restrictions for the public are the urgent needs of the hour to protect the future of the country and its people from another COVID-19 tsunami [43].

Results

A chronological overview of the contributions of different regions of India towards the cases and fatalities in the two waves of the COVID-19 pandemic

The chronological variations in the number of new cases and new deaths in India (Figures 1A and 1B) and the contributions of different regions towards the total cases and fatalities of the nation are noteworthy. At the beginning of the first wave, the SR accounted for nearly 40% of the nations’ total cases in March 2020. From April 2020 till June 2020, the WR remained the major contributor of COVID-19 cases of the nation (43%, 46%, and 31% of the total cases respective in these months). Subsequently from June 2020, when the first phase of unlocking (unlock-1) started in the country (Figure 1A), till the end of October 2020, the SR contributed 41%, 40%, 34%, and 41% of the total COVID-19 cases of India in the respective months. In November 2020, the NR was the major contributor (31%), whereas from December 2020, till February 2021, SR again contributed respectively 31%, 47%, and 43% of the total cases of the nation. At the beginning of the rising phase of the second wave, from March 2021 till April 2021, the WR contributed about 63%, and 30% of the nations' total cases respectively, and in May 2021, the SR became the major contributor of new cases (42%) in the country (Figure 1C).

Figure 1: Chronological variations of cases and deaths during the first and second COVID-19 wave in India: Variations in numbers of the daily cases (A) and deaths (B) during the first and second wave of the COVID-19 pandemic (from January 30th , 2020 to May 29th , 2021) in India are represented using the bar graphs. The next set of bar graphs are representing the chronological variation, during the months of the first and second waves, in contributions of the different regions of India towards the total percentages of COVID-19 cases (C) and deaths (D). The pie charts are denoting the total contributions of the different regions of India to the total percentages of cases (E) and deaths (F) during the first and second waves of the pandemic in the country.

In terms of fatality, the WR accounted for the highest monthly fatality from March 2020 till October 2020 (contributed nearly 35%, 59%, 62%, 51%, 41%, 37%, 39%, and 31% of the total monthly deaths of the nation respectively) (Figure 1D). The NR contributed over 33% and 31% of total fatality in November and December 2020, and the WR was the highest monthly contributor of COVID-19 related fatality from January 2021 till April 2021 (30%, 40%, 39%, and 33% of the total fatality in the respective months). However, in May 2021, the SR accounted for the maximum proportion of fatality of the country (28%) (Figure 1D). Thus, it can be inferred from these results that both the Western and Southern Indian states have been the major hotspots of the COVID-19 pandemic in the Indian subcontinent (Figures 1E and 1F)

The first wave of COVID-19 in India-A detailed analysis

Apart from Kerala, most of the Indian states reported their first COVID-19 infection in March or April 2020. The Government of India has implemented a nationwide complete lockdown and strict containment protocols from March 25^th, 2020 to combat the dissemination of the viral infection. The unlock process, implemented in six phases, commenced from June first, 2020 to November 30^th, 2020, although the daily cases began to surge steadily, especially from the end of May 2020 to September 2020 in the majority of Indian states (Table 1) [25]. The adverse effects of unlocking can be understood from the following statistics – from the week, before the last week of lockdown (May 18^th, 2020 to May 24^th, 2020) to the week, after one continuous week of unlock-1 (June 8^th, 2020 to June 14^th, 2020), the change in weekly-average numbers of new confirmed cases, active cases, and deaths respectively showed an increase from 6369 to 11170 (1.75-fold), from 3153 to 4048 (1.28-fold), and from 144 to 340 (2.35-fold) (analysis not shown). India reported the maximum number of daily new cases on September 16^th, 2020 (around 98,000) and the maximum active cases on September 17^th, 2020 (1018454), which was marked as the peak of the first wave. Subsequently, the figures of daily cases started to drop steadily in the following weeks, till the end of January 2021, when the number reduced around 10,000 cases/day; marking the trough of the wave. Among the 10758629 cases reported during the first wave, the highest number of cases was reported from SR (3933360), contributing 36.5% of the total cases where the state of Karnataka was the top contributor (~8.7%) (Table 1). The WR contributed 21.6% of the nation’s total cases, where the top contributor was Maharashtra (2026399 cases, ~18.8%). The NR accounted for about 16.4% of total cases, where the highest contributor was Delhi (5.9%). The ER shared 11.8% of the total cases, where West Bengal contributed maximally (~5.3%). The CR reported 10.7% of the total cases in which Uttar Pradesh contributed the majority of cases (5.5%). The NER was the lowest contributor of cases (3%) in the first wave where Assam contributed the major number of cases (2%) (Table 1). The CCR was found to be highest in Ladakh (3352 cases/1 lakh of the population), followed by Delhi (3175) and Chandigarh (1773).

In addition to contributing to the second-highest number of COVID-19 cases, states of the WR also contributed the maximum number of deaths during the first wave (accounted for 36.4% of the nation’s total deaths of 154428). The state of Maharashtra accounted for the most number of deaths in the region (33%). The trend also remained similar for the SR, which accounted for 24.4% of the nation’s total deaths (Table 1). Contributions from the Northern states were about 17.7% to the total fatalities of the nation (Table 1), whereas, the CR and ER respectively accounted for 10.5% and ~9.5% of the total deaths (b). The NER states reported the least mortality and contributed only ~1.51% of the total deaths of the nation (Table 1). The highest CDR was however reported by the national capital, Delhi (54/1 lakh of the population), followed by Goa (50), Ladakh (45), and Maharashtra (42) (Table 1). The CFR was found to be highest in the state of Punjab (3.24) in the NR, followed by Maharashtra (2.5) in the WR with Sikkim (2.18) stands next from the NER. The state of West Bengal (1.785) accounted for the highest CFR from the ER, followed by Uttarakhand (1.71), Delhi (1.71), and Himachal Pradesh (1.69) from the NR. Among the states of Southern India, Puducherry recorded the highest CFR (1.66) (Figures 2A and 2C and Figures 3A and 3C) (Table 1).

Figure 2: Maps of COVID-19 cumulative cases and deaths for the Indian states and UTs during the two waves: Different states and union territories (UTs) of India are color-coded to represent their different cumulative case rates during the first (A) and second wave (B) of the pandemic. Similarly, the differences in cumulative death rates for the states and UTs are represented for the first (C) and second wave (D).

Figure 3: Maps of case fatality ratio and test per case for the Indian states and UTs during the two waves: Different states and union territories (UTs) of India are color-coded to represent their different case fatality ratios during the first (A) and second wave (B) of the pandemic. Similarly, the differences in test per case (test-to-case ratio) for the states and UTs are represented for the first (C) and second wave (D).

Regarding the testing of cases, until the end of January 2021, we found that more than 228.4 million COVID-19 tests were performed all over India. The WHO has recommended an optimum of 30 test-to-case ratios (T: C) as standard; however apart from the states and UT, like Jammu and Kashmir (36.5), Uttar Pradesh (46.6), Gujarat (42), Bihar (80.5), Jharkhand (44), Assam (29.7), Mizoram (48), and Andaman and Nicobar Islands (44), all other states and union territories had a T: C ratio less than the WHO recommended mark [26] (Table 1).

The second wave of COVID-19 in India: A detailed analysis

The period between the end of February 2021 and early March 2021, marked the rising phase of the catastrophic second wave of the COVID-19 pandemic in India. During this period, the country reported more than 3 lakhs new cases/day in April that soared to over 4 lakhs cases/day and over 4000 daily deaths in the first week of May 2021, which abruptly overburdened the healthcare system of the country. On May 6^th, 2021, India reported its highest number of over 414280 new cases in a day, which marked the peak of the second wave until now. Thereafter, the daily cases started to decrease gradually, however the fatality rate remained high.

Starting from February first till May 29^th, 2021, India reported a total number of 17134975 cases and over 1.7 lakh deaths. Until May 29th, 2021, the SR remained the top contributor of cases (32%) and also accounted for 22% of the country’s fatality, where the state of Karnataka (9.5%) and Kerala (9.1%) together accounted for more than half of the total cases of the region, and Karnataka (9.3%) and Tamil Nadu (6.3%), like in the first wave, were also the major contributors to the nation’s fatalities (Table 2). The WR contributed over 25% and 29% of the cases and fatalities respectively during this period. The NR, CR, and ER contributed 16%, ~13%, and ~10.8% respectively to the total cases, and 27%, 14.5%, and 7.7% to the nation’s total deaths respectively. The NER reported the least number of cases (1.63%) and fatalities (2%) in the country (Table 2).

Until May 29^th , 2021, the highest CFR was reported by Andaman and Nicobar Islands (2.59), followed by Punjab (2.23) from the NR and Nagaland (2.22) from the NER. The highest CDR was found for Goa (118 deaths/1 lakh), followed by Uttar Pradesh (51), and Lakshadweep (45). Lakshadweep was also found to contribute highest to the CCR (11084 cases/1lakh), followed by Uttar Pradesh (4835) and Chandigarh (3289). It is noteworthy that regarding test per case, apart from Andaman and Nicobar Islands (86.2), Haryana (49), and Ladakh (29.1), all other states and union territories were lagging behind the recommended WHO level26 (Figures 2B and 2D and Figures 3B and 3D).

One of the other major contrasts between the first and second waves is the evolution of new variants of the novel SARS-CoV-2 virus during the second wave. The three imported viral variants of concern that have been identified in India are the UK (B.1.1.7) variant, the South African (B.1.351) variant, and the Brazilian (P1) variant, among which the B.1.1.7 variant was predominantly present in Delhi and Punjab in April 2021. Among the two novel variants of India, the highly contagious B.1.617.2 (Delta) variant from Maharashtra has started evolving rapidly and overtook the B.1.618 variant in West Bengal, and eventually became the major variant in most of the states. The WHO has already designated the delta variant as a 'variant of concern' in May 2021. This variant has spread in all states across the nation and is identified as one of the major causes of the calamity associated with the second wave of COVID-19 in India, as per the study conducted by the Indian SARS-CoV-2 Genomics Consortium (INSACOG), which was launched by the Ministry of Health and Family Welfare, Govt. of India, on December 30^th, 2020 [27,28].

Roles of some major mass-scale public events, during the second wave, on COVID-19-related outcomes

Mass-scale public gatherings, like Kumbh Mela 2021 (9 million participants) and the state elections (covering 243 million residents) have contributed to the escalated spreading of the second wave in the nation [29,30]. A 117-fold increase in the number of weekly- average new cases and a 266-fold increase in the weekly-average new deaths were found for the state of Uttarakhand when we compared the data between before and after the festival of Kumbh Mela 2021. Uttar Pradesh, like Uttarakhand, also showed a sharp jump in the weekly average new cases and deaths – respectively a 240-fold and 201-fold increase in the numbers of new cases and deaths after this religious festival (Table S1 and Figure S1). These numbers are much higher than the fold-increase found for the new cases (20.9-fold) and new deaths (35.4-fold) for the entire nation between the mentioned periods. Four Indian states, Assam, Kerala, Tamil Nadu, West Bengal, and one UT, Puducherry, that witnessed their ‘legislative assembly general elections’ (LAGEs) from the end of March to the end of April 2021, also reported a substantial increase in the average daily cases after the elections compared to some of the other states with no LAGE or major public gatherings during the same period (Table S2 and Figure S2). These increases in numbers are mainly attributed to the election- related rallies and mass-scale public meetings which were organized by the local political parties [31]. However, it is noteworthy that we could not dissect out the exact contributions of such gatherings from the general increase in the numbers of cases and deaths due to aggravation of the pandemic itself using the available data.

Conclusion

The study comprehends the chronological heterogeneity in the patterns of pandemic progression and the severity of the second wave over all the states of the country, highlighting the major hotspot regions and some gaps in mitigation strategies.

Funding Conclusion

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Acknowledgements

SD (CSIR-RA) is thankful to the Council of Scientific and Industrial Research, Government of India, for the fellowship, Post-doctoral Research Associateship (award no. 09/677(0055)/2020-EMR-I). KA and DC are thankful to TIET-VT-CEEMS for research fellowships. NKC is thankful to Thapar School of Liberal Arts & Sciences for the Director’s Discretionary Fellowship.

Conflict of Interests

The authors declare no conflict of interests.

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